Thermostatic valve device having non-linear flow characteristics

ABSTRACT

A thermally responsive valve device having non-linear flow characteristics. The thermally responsive valve device includes movable and stationary valve structure. A movable valve member is movable to adjust the open area of a flow passage, but movement of the movable valve member provides a non-linear relationship between the area of the flow passage created and the distance of travel of the movable valve member. The movable and/or the stationary valve member is provided with an irregularly shaped portion so that with slight opening movement of the movable closure member less fluid flow than normal is permitted. As the movable valve member continues to move in an opening direction, the fluid flow increases at a predetermined non-linear rate until a specific flow rate is achieved. This operating characteristic eliminates or dramatically reduces temperature fluctuations in the system.

RELATED APPLICATION

This application is a continuation-in-part of U.S. application Ser. No.384,519, filed Aug. 1, 1973, now U.S. Pat. No. 3,893,618.

BACKGROUND OF THE INVENTION

Thermally responsive valve devices are employed as the principaltemperature control means in engine cooling systems. It is well known inthe art that existing thermostatic valve devices during initial openingoperation permit the temperature of the system controlled to fluctuate.Such fluctuations are undesirable. In an attempt to solve this problem,some thermally responsive valve devices have included means forregulating fluid flow at low fluid rates. U.S. Pat. Nos. 2,926,853 and3,182,911 disclose thermally responsive valve devices which havemultiple closure members. However, such multiple closure members, eventhough providing fluid control, do not provide good metering or fineregulation of fluid flow, required for temperature control stabilityunder dynamic operating conditions.

It is an object of this invention to provide a thermally responsivefluid valve device which has such excellent regulation of fluid flow.

Other objects and advantages of this invention reside in theconstruction of parts, the combination thereof, the method ofmanufacture, and the mode of operation, as will become more apparentfrom the following description.

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS

FIG. 1 is a longitudinal sectional view of a thermally responsive valvedevice of this invention in which a movable valve member is movable toadjust the area of a flow passage and in which movement of the movablevalve member provides a non-linear relationship between the area of theflow passage and the distance of travel of the movable valve member.

FIG. 2 is a fragmentary elevational view of the thermally responsivevalve device of FIG. 1, showing the valve device in a slightly openposition.

FIG. 3 is a fragmentary elevational view, with parts shown in section,of the valve portion of another thermally responsive valve device ofthis invention.

FIG. 4 is a longitudinal sectional view of another thermally responsivevalve device of this invention.

FIG. 5 is a fragmentary elevational view of the valve portion of thedevice of FIG. 4, showing the valve device in a slightly open condition.

FIG. 6 is a fragmentary sectional view of the valve portion of anotherthermally responsive valve device of this invention.

FIG. 7 is a longitudinal sectional view of another thermally responsivevalve device of this invention.

FIG. 8 is a fragmentary elevational view, with parts shown in section,of the valve portion of the device of FIG. 7, showing the valve devicein slightly open condition.

FIG. 9 is a fragmentary perspective view, with parts shown in section,of the valve portion of another thermally responsive valve device ofthis invention, showing the valve elements in a slightly open condition.

FIG. 10 is a fragmentary sectional view showing a part of the valveportion of another thermally responsive valve device of this invention.

FIG. 11 is a fragmentary sectional view showing the valve portion of thethermally responsive valve device of FIG. 10, showing the valve elementsin a slightly open condition.

FIG. 12 is a fragmentary sectional view showing a part of the valveportion of another thermally responsive valve device of this invention.

FIG. 13 is a fragmentary sectional view showing the valve portion of thethermally responsive valve device of FIG. 12, showing the valve portionin a slightly open condition.

FIG. 14 is a fragmentary sectional view showing a part of the valveportion of another thermally responsive valve device of this invention.

FIG. 15 is a fragmentary sectional view showing the valve portion of thethermally responsive valve device of FIG. 14, showing the valve portionin a slightly open condition.

FIG. 16 is a longitudinal sectional view of another thermally responsivevalve device of this invention.

FIG. 17 is an enlarged fragmentary sectional view of a portion of thedevice as shown in FIG. 16, during opening operation of the valvedevice.

FIG. 18 is a sectional view taken substantially on line 18--18 of FIG.17.

FIG. 19 is fragmentary sectional view similar to FIG. 17, but showingelements of the device during further opening operation of the valvedevice.

FIG. 20 is a sectional view taken substantially on line 20--20 of FIG.19.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 and 2 show a thermally responsive valve device of this inventionin which a stationary member 20 has an annular valve seat portion 22forming a fluid port. The valve seat portion has an annular flange 23forming a recess. The stationary member 20 has an arm 24 which supportsa thermally responsive actuator member 26, which may be of any suitabletype, such as, for example, the type shown in U.S. Pat. Nos. 2,806,375and 2,806,376.

A helical spring 30 encompasses the actuator member 26 and joins theactuator member 26 to a connector member 32, which is engaged by thespring 30. The connector member 32 extends through the fluid port in thestationary member 20 and is joined by a link 34 to an actuator stem 36of the actuator member 26. The link 34 is shown as encompassing theactuator stem 36 and is engaged by a helical spring 38 which encompassesthe stem 36 and engages an arm 40 which is carried by the stem 36. Thearm 40 engages a nut 41 which is attached to the stem 36. The arm 40extends from the stem 36 and joins a movable valve member in the form ofa cup 42 which has an open upper end 44 and an annular closure portion45 at the lower part thereof. The cup 42 is slidably encompassed by ahorizontal wall 46.

The closure portion 45 of the cup 42 normally seats within the recessformed by the flange 23 in the valve seat portion 22, as showin inFIG. 1. The upper edge of flange 23 of the valve seat portion 22 hasdownwardly inclined or tapered portions 50 at opposite parts thereof.

Operation

The thermally responsive valve device of FIGS. 1 and 2 is of the typereferred to as a by-pass valve device. Normally fluid flow existsthrough the device from the bottom to the top, as illustrated by arrows52 in FIG. 1. Thus, fluid flows from the device outwardly through theupper open end 44 of the cup 42, and the fluid discharges to a regionabove the horizontal wall 46.

Some of the fluid which flows upwardly through the valve device engagesthe thermally responsive actuator member 26. If the temperature of thefluid which engages the thermally responsive actuator member 26 is abovea given predetermined temperature, the actuator stem 36 moves upwardlyand moves the cup member 42 upwardly. Such movement is against theforces of the spring 30.

As the cup 42 moves upwardly, the closure portion 45 thereof slidablymoves upwardly within the flange 23. Due to the fact that the upper edgeof the flange 23 has downwardly tapered portions 50, the lower edge ofthe cup 42 first moves past the lowermost part of the downwardly taperedportions 50. Thus, a small opening is first created at the lowermostpart of each of the downwardly tapered portions 50 at the upper edge ofthe flange 23, and fluid flows outwardly therefrom, as illustrated byarrows 56 in FIG. 2. As the cup 42 continues to move upwardly, the fluidpassage provided at each of the downwardly inclined parts 50 becomesgradually greater, and greater fluid flow between the cup 42 and thevalve seat portion 22 is permitted. The fluid flows outwardly from thevalve device into the space between the stationary member 20 and thehorizontal wall 46. Ordinarily, means are provided by which upwardmovement of the cup 42 closes a port immediately above the cup 42, sothat following maximum movement of the cup 42 upwardly, all of the fluidflowing through the fluid port within the stationary member 20 flowsoutwardly between the stationary member 20 and the cup 42.

When the temperature of fluid which engages the actuator member 26decreases, the actuator stem 36 and the cup 42 are moved downwardly bythe spring 30.

FIG. 3

FIG. 3 shows another embodiment of the thermally responsive valve deviceof this invention. A stationary member 60 is provided with a fluid port62. An arm 64 attaches a thermally responsive actuator member 66 to thestationary member 60. The stationary member 60 has a valve seat portion67, provided with an annular flange 68. The flange 68 has an upper edgeportion 69 which is straight or level. In a manner similar to thatdisclosed with respect to the embodiment of FIGS. 1 and 2, a cup member70 is slidably positioned inside of the flange 68. The lower edge of thecup 70 is generally level but is provided with one or more upwardlyinclined surfaces 72, which form one or more notches in the lower edgeof the cup 70. Thus, as the actuator member 66 moves the cup 70 upwardlywithin the flanges 68, initial movement of the cup 70 upwardly creates avery small fluid passage in the notch formed by the surfaces 72. As thecup 70 continues to move upwardly, the fluid passage provided betweenthe cup 70 and the upper edge 69 of the flange 68 gradually increases.

FIGS. 4 and 5

FIGS. 4 and 5 show another embodiment of the thermally responsive valvedevice of this invention. A stationary member 80 is provided with avalve seat portion 81 which has a flange 82 having an upper edge whichis provided with one or more downwardly inclined surfaces or portions84. A movable closure member 86 is adapted to seat within the valve seatportion 81 and within the flange 82 to prevent flow of fluid upwardlyfrom the thermally responsive device. The closure member is attached toa thermally responsive actuator 88 by means of a connector member 90 anda spring 92. The thermally responsive actuator member 88 is attached tothe stationary member 80 by means of an arm 94. Upon increase intemperature of fluid engaging the thermally responsive actuator 88, themovable closure member 86 is moved upwardly by the actuator 88. Fluidfirst flows through a small fluid passage which is provided between themovable closure member 86 and the lowermost part of the downwardlyinclined surface or portion 84 at the upper edge of the flange 82, asillustrated by an arrow 100 in FIG. 5. As upward movement of the movableclosure member 86 continues, a gradually increasing fluid passage iscreated.

FIG. 6

FIG. 6 shows another thermally responsive valve device of thisinvention. A stationary member 110 has a valve seat portion 112 providedwith a flange 113 which has a level upper edge 114. A movable closuremember 115 normally seats within the valve seat portion 112 and withinthe flange 113. The movable closure member 115 has a lower edge surface116, a part of which is upwardly inclined. Thus, as a thermallyresponsive actuator member 120 moves the movable closure member 115upwardly, as illustrated in FIG. 6, initial movement of the movableclosure member 115 upwardly provides a very small fluid passage betweenthe upper-most part of the lower edge surface 116 of the movable closuremember 115 and the upper edge 114 of the valve seat portion 112.

FIGS. 7 and 8

FIGS. 7 and 8 show another embodiment of a thermally responsive valvedevice of this invention. The thermally responsive valve device in FIGS.7 and 8 is provided with a stationary member 130 which has a lowerportion thereof which is provided with an annular valve seat portion132, within a flange 133. A bridge 134 extends slightly upwardly fromthe stationary member 130 and has attached thereto an actuator stem 136of an actuator device 138. Attached to the actuator device 138 is aclosure member 140. The lower edge surface of the valve seat portion 132has an upwardly inclined portion 142. When the thermally responsiveactuator 138 senses temperatures above a predetermined value, thethermally responsive actuator 138 moves downwardly and moves the closuremember 140 downwardly. Initial movement of the valve closure member 140downwardly creates a slight flow passage between the vertex of theinclined edge portion 142 of the valve seat portion 132 and the upperedge of the closure member 140 and fluid flows therefrom as illustratedby an arrow 146 in FIG. 8. Further downward movement of the closuremember 140 creates a gradually increasing fluid flow passage between thevalve seat portion 132 and the closure member 140, as illustrated inFIG. 8.

FIG. 9

FIG. 9 shows another embodiment of the thermally responsive valve deviceof this invention. A stationary member 150 is provided with a valve seatportion 152 having an annular flange 153. A closure member 154 normallyseats within the valve seat portion 152 and within the annular flange153.

The upper edge of the closure member 154 has one or more downwardlyinclined portions 156. Thus, as a thermally responsive actuator member158 moves the closure member 154 downwardly, initially a very small flowpassage is created between the downwardly inclined edge 156 of theclosure member 154 and the lower edge surface of the valve seat portion152, as illustrated in FIG. 9.

FIGS. 10 and 11

FIGS. 10 and 11 show a modification in the valve seat portion of athermally responsive valve device of this invention. A stationary member160 is provided with a valve seat portion 162 having an annular flange164. The inner surface of the annular flange 164 has an inclined wallsurface or upwardly sloping portion 165 along at least a part thereof.An actuator member not shown, is attached to a closure member 166 formovement thereof. Initial upward movement of the closure member 166within the flange 164 provides a very small flow passage along at leasta portion of the periphery of the closure member 166, between thesloping portion 165 and the lower edge of the closure member 166. As theclosure member 166 moves gradually upwardly, the spacing between theinclined wall surface 165 and the lower edge of the closure member 166gradually increases and provides a gradually increasing fluid flowpassage for flow of fluid between the lower edge of the closure member166 and the inclined surface 165 of the valve seat portion 162, asillustrated in FIG. 11.

FIGS. 12 and 13

FIGS. 12 and 13 show another modification in the valve seat portion of athermally responsive valve device of this invention. A stationary member170 has a valve seat portion 172 provided with an annular flange 173which has an upwardly curved or arcuate inner surface 174 along at leasta portion of the flange 173. A movable closure member 176 is adapted toseat within the valve seat portion 172. As a thermally responsiveactuator member, not shown, moves the movable member 176 upwardly,initial movement of the closure member 176 upwardly results in verylimited fluid flow, at least at a portion of the lower surface or edgeof the closure member 176. As illustrated in FIG. 13, further upwardmovement of the closure member 176 permits increased fluid flow betweenthe closure member 176 and the valve seat portion 172. Such flow is in apattern which is different in characteristics from the flow patternobtained as the closure member 166 moves upwardly with respect to thevalve seat 162 in the device shown in FIGS. 10 and 11.

FIGS. 14 and 15

FIGS. 14 and 15 show another modification in the valve seat portion of athermally responsive valve device of this invention. A stationary member180 is provided with a valve seat portion 182. The stationary member 180also has an inclined or tapered entry portion 184 directly below thevalve seat portion 182. A movable closure member 186 is adapted to seatwithin the valve seat portion 182. As the movable closure member 186moves slightly upwardly from the valve seat portion 182, a very smalland controlled fluid flow passage is created between the closure member186 and the valve seat portion 182. The inclined portion 184 which leadsto the valve seat portion 182 provides a type of flow pattern betweenthe closure member 186 and the valve seat portion 182 which is nototherwise obtained.

FIGS. 16-20

FIGS. 16-20 show another embodiment of the thermally responsive valvedevice of this invention, which may be generally similar to that shownin U.S. Pat. No. 3,858,800. A support member 200 and a support member204 have annular flange portions 206 and 208, respectively, which arejoined together at the walls of a fluid conduit 212.

The support member 200 has an annular valve seat portion 216, forming afluid port. The annular valve seat portion 216 is engageable by a flange220 of a movable valve member or movable closure member 222, to closethe fluid port formed by the valve seat portion 216. The movable valvemember 222 is attached to a container portion 228 of a thermallyresponsive actuator 230, of the type discussed above and havingthermally responsive actuator material therein. A coil spring 231encompasses the container portion 228 and engages the support member 204and the movable closure member 222 and urges the movable closure member222 toward the valve seat portion 216. The container portion 228 isencompassed by a guide portion 232 of the support member 204 and isaxially movable therewithin.

Extending from the container portion 228 is a rod 240. The containerportion 228 is movable with respect to the rod 240. The rod 240 issecured to the support member 200.

Attached to the support member 200, integrally or otherwise, is a fluidflow control ring 250 provided with an inclined wall 252 having aplurality of spaced-apart inclined notches 254 in the surface thereof.Each of the notches 254 has sloping upper edge surfaces 258. Herein thering 250 is shown as being retained in engagement with the annular valveseat portion 216 by a protuberance or rib 259 of the support member 204.Thus, as the movable valve member 222 initially moves from the valveseat portion 216, fluid can flow only through openings formed betweenthe flange 220 and the edge surfaces 258 of the notches 254, asillustrated by arrows 260 in FIGS. 17 and 18. Thus, initially there isonly very limited fluid flow. As the movable valve member 222 movesfurther from the valve seat 216, the notches 254 provide increasinglygreater fluid flow, as illustrated by arrows 266 in FIGS. 19 and 20.With increased movement of the movable valve member 222 the flange 220moves from the notches 254 and there is fluid flow completely past thecomplete periphery of the flange 220.

SUMMARY

It is to be understood that the vertex in any of the inclined portionsor notches discussed above and shown in the drawings may have a definitepoint, or the vertex may be an extending upper or lower part of thesurface which is less definable. The thermally responsive valve deviceof this invention provides means by which initial fluid flow through athermally responsive valve device can be controlled and regulated on apredetermined basis to provide non-linear metering of the fluid flow.Such metering or accurate regulation of the fluid flow provides a muchmore stable temperature control than could otherwise be obtained in athermally responsive valve device. Furthermore, such accurate fluid flowcontrol and regulation permits great flexibility and possibilities inthe modification of total temperature control range of a thermallyresponsive valve device.

It is also to be understood from the embodiments of this invention asdisclosed herein that various types of notches or inclined portions orarcuate portions may be provided on valve seat portions or on closuremembers in numerous types of thermally responsive valve structures ofthis invention. Furthermore, the inclined or tapered or arcuate portionswhich provide a very small opening at initial movement of a closuremember, may have various angles, slopes, or inclinations or edgecurvature or the like. Furthermore, one or more inclined or curved edgesurfaces may be provided in a stationary member and/or in a movableclosure member in order to provide fine metering or regulation of fluidflow through more than one opening or a plurality of openings, as aninclined surface or curved surface structure exists in a movable closuremember and/or in a stationary closure member. Thus, a thermallyresponsive valve device of this invention includes structure by whichmovement of a movable valve member provides a non-linear relationshipbetween the area of the fluid passage created and the distance or lengthof travel of the movable valve member.

Although the preferred embodiment of the device has been described, itwill be understood that within the purview of this invention variouschanges may be made in the form, details, proportion and arrangement ofparts, the combination thereof, and mode of operation, which generallystated consist in a device capable of carrying out the objects setforth, as disclosed and defined in the appended claims.

The invention having thus been described, the following is claimed:
 1. Athermally responsive fluid flow control valve device for elimination oftemperature fluctuations in the fluid during initial opening operationcomprising:a stationary valve member having an annular valve seatportion forming a fluid port, a movable valve member having a closureportion engageable with the annular valve seat portion to close thefluid port, the movable valve member being movable to move the closureportion toward and away from the valve seat portion of the stationaryvalve member, the stationary valve member having an annular flangeencompassing the valve seat portion and forming a recess within whichthe annular valve seat portion is located and within which the closureportion of the movable valve member is movable, the annular flangehaving a sloping part, initial movement of the movable valve member withrespect to the stationary valve member thus creating a small fluid flowpassage between the flange and the movable valve member, and increasedmovement of the closure portion of the movable valve member adjacent theannular flange being non-linear in magnitude with respect to the area ofthe fluid flow passage created between the annular flange and themovable valve member, thermally responsive actuator means, means joiningthe thermally responsive actuator means to the movable valve member formovement thereof.
 2. The thermally responsive fluid flow control valvedevice of claim 1 in which the annular flange has an end surface spacedfrom the valve seat portion, the end surface having a sloping part. 3.The thermally responsive fluid flow control valve device of claim 1 inwhich the flange has a sloping wall surface which extends angularly fromthe valve seat portion.
 4. The thermally responsive fluid flow controlvalve device of claim 1 in which the movable valve member is a hollowcylindrical member.
 5. The thermally responsive fluid flow control valvedevice of claim 1 in which the movable closure member is a substantiallyflat element.
 6. Thermally responsive fluid flow control mechanism ofthe type having a stationary valve member provided with a wall portionhaving a cylindrical internal surface, a movable valve member having acylindrical portion slidably engageable with the cylindrical internalwall surface of the stationary valve member, the improvement wherein thewall portion of the cylindrical portion of the stationary valve memberhas a notch part so that as the movable valve member moves in adirection from the stationary valve member a small opening is createdfor fluid flow in the notch part between the movable valve member andthe stationary valve member and increased movement of the movable valvemember in a direction from the stationary valve member creates a greateropening for fluid flow between the stationary valve member and themovable valve member,thermally responsive actuator means, and meansjoining the thermally responsive actuator means to the movable valvemember for movement thereof.
 7. A thermally responsive fluid flowcontrol valve device for elimination of temperature fluctuation in thefluid during initial opening operation comprising:a stationary valvemember having an annular valve seat portion forming a fluid port, amovable valve member having a closure portion engageable with the valveseat portion to close the fluid port, said portions of the valve membersbeing in overlapping relationship, said portion of one of said valvemembers having an inclined wall surface which extends from the annularvalve seat portion, initial movement of the movable valve member in adirection away from the stationary valve member thus creating a smallfluid flow passage between said portions of the valve members andincreased movement of the movable valve member in a direction from thestationary valve member being non-linear in magnitude with respect tothe magnitude of the fluid flow passage created between the saidportions of the valve members, thermally responsive actuator means,means joining the thermally responsive actuator means to the movablevalve member for movement thereof.